Integrated circuit devices with a high integration factor are manufactured using specific processing technology. Such devices are more and more occupying less space due to improved process technology. With decreasing process geometry, the operating voltage or core voltage in such devices is also reduced. While it was common to use a supply voltage of e.g. 5 Volts, newer devices use only 3.3 Volts or even less. At 0.18 μm process technology, the internal core voltage is 1.8 Volts. Other technologies may reduce the voltage even further, for example to 1.2 Volts. While circuit boards are often designed using 3.3V or 5V as the supply voltage, many integrated devices generate the internal core voltage of, for example 1.8 volts or even lower core voltages by means of an integrated voltage regulator. Such voltage regulators are traditionally linear regulators. Thus, an input power loss which is converted into heat by the linear voltage regulator of up to 45% ((3.3V−1.8V)/3.3V=45%) can occur. This waste of energy can moreover be significant in any battery operated device.
Hence, there exists a need for an improved integrated circuit device.